Conventional insulation packets for thermally and acoustically insulating an aircraft fuselage consist for the most part of voluminous nonwoven materials, which are used in matte form, comprise attachment openings through which retainers are passed, and can be easily compressed during attachment to the fuselage structure by means of attachment clips to be secured to the retainers. To prevent moisture from penetrating into the insulation material, use is made of sheathing films that incorporate ventilation holes to enable pressure compensation and prevent damage to the film when installing the insulation packet. At the same time, the ventilation holes prevent the insulation packets from expanding in flight given a drop or rise in cabin pressure.
During a prolonged flight, condensation water accumulates inside of such insulation packets, which primarily has two essential causes. On the one hand, the insulation packets can directly abut the inside of the structure of the aircraft fuselage, which is coated with a thin film of condensation water after practically every flight. On the other hand, moist air makes its way into the insulation packets as the result of convective effects and diffusion by way of the ventilation holes and also diffusion through the closed sheathing film, where they lead to water condensation when the incoming air drops below the dew point during flight owing to the low temperatures of the aircraft fuselage. To remove the condensation water, drainage holes are often incorporated on the bottom of the insulation packets, but are only effective under certain conditions, since part of the condensation water gets retained in the form of drops on the pores or fibers of the insulation material. Furthermore, additional moist air gets into the insulation packets through the drainage holes, which can accelerate water condensation in the insulation even more. In the end, this leads to extra weight in the aircraft and accelerated ageing of the insulation.
EP 1 124 720 B1 and US 20040175516 A1 show an insulation arrangement for insulating the interior of an aircraft with insulation packets, which are completely enveloped by film that allows the diffusion of gases.
In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.